You dont create PTR records for a domain, you create them for a subnet. 1.2.3.4 can have a PTR record of xyz.domain.com and 1.2.3.5 can have a PTR record of bleh.blah.com. It's not tied up to domains.
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pauskaDec 28 '11 at 12:39

the /24 is the bits for the subnet mask. Meaning 255.255.255.0 for your particular case.
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Split71Dec 28 '11 at 14:00

1 Answer
1

PTR records are a special case. Whoever supplies your IP addresses (usually your host/ISP), must do one of the following:

Set up your reverse DNS entries on their DNS servers.

Delegate authority" for your reverse DNS entries to your DNS servers.

This has to do with the unique nature in which reverse DNS is resolved.

I would contact your host to resolve this and disable/remove the PTR records on the Plesk system.

Another note about reverse DNS is that it is a 1:1 mapping. You should not have multiple PTR records mapping an IP to a domain. In contrast, you can have multiple A records mapping different domains to the same IP.